the “snow covered dunghill” comment was probably because Luther was disgusted at the moral decadence of Rome when he visited there. Luther was personally a holy roller (though he didn’t find any problem with the institution of marriage as applied to the clergy). He was also somewhat of a freedom fighter by nature, and prone to hyperbolic statements.
I’m sure his constant fights with Catholics (after he initiated the reformation) dug him into an exceedingly aggressive stance against the church. Like in any war as the fight rolls on any army or military leader becomes more aggressive in their tactics. There’s only two ways wars are won … either with diplomacy or defeating the other army (by killing them in such a brutal fashion that they lose their will to fight).
Diplomacy, however, requires concession (and the idea that both parties win). The Catholic reaction to Luther’s complaints were hardly diplomatic or conciliatory. Rather the response was aggressive, which only drew an exceedingly aggressive response by the reformers. This is human nature whether you guys admit it to yourselves or not!
Well, if the Catholic reaction was “hardly diplomatic or conciliatory” at times, it was because his views were heretical. So yes, there may have been some anger on the part of some Church members. But if recollection serves me right, the Catholic Church had given several chances for Luther to debate and dialogue his views with other Church members. This was done, as a way for the CC, to show Luther he was in error. He was excommunicated after several unsuccessful attempts by the Church to get Luther to recant his heretical views.
And the whole snow-covered dung hill analogy was not inspired by the wickedness he had seen in Rome, but rather his own scrupulosity:
"Like every victim of scrupulosity, he saw nothing in himself but wickedness and corruption. God was the minister of wrath and vengeance. His sorrow for sin was devoid of humble charity and childlike confidence in the pardoning mercy of God and Jesus Christ.
This anger of God, which pursued him like his shadow, could only be averted by “his own righteousness”, by the “efficacy of servile works”. Such an attitude of mind was necessarily followed by hopeless discouragement and sullen despondency, creating a condition of soul in which he actually “hated God and was angry at him”, blasphemed God, and deplored that he was ever born. This abnormal condition produced a brooding melancholy, physical, mental, and spiritual depression, which later, by a strange process of reasoning, he ascribed to the teaching of the Church concerning good works, while all the time he was living in direct and absolute opposition to its doctrinal teaching and disciplinary code.
Of course this self-willed positiveness and hypochondriac asceticism, as usually happens in cases of morbidly scrupulous natures, found no relief in the sacraments. His general confessions at Erfurt and Rome did not touch the root of the evil. His whole being was wrought up to such an acute tension that he actually regretted his parents were not dead, that he might avail himself of the facilities Rome afforded to save them from purgatory. For religion’s sake he was ready to become “the most brutal murderer”, “to kill all who even by syllable refused submission to the pope” (Sämmtliche Werke, XXXX, Erlangen, 284). Such a tense and neurotic physical condition demanded a reaction, and, as frequently occurs in analogous cases, it went to the diametric extreme.
The undue importance he had placed on his own strength in the spiritual process of justification, he now peremptorily and completely rejected. He convinced himself that man, as a consequence of original sin, was totally depraved, destitute of free will, that all works, even though directed towards the good, were nothing more than an outgrowth of his corrupted will, and in the judgments of God in reality mortal sins. Man can be saved by faith alone.
Our faith in Christ makes His merits our possession, envelops us in the garb of righteousness, which our guilt and sinfulness hide, and supplies in abundance every defect of human righteousness."
newadvent.org/cathen/09438b.htm
You know the whole “whore of Babylon” and “anti-christ” bit the CC (which by the way is an insult to all us Catholics) has been branded with (labeled as such by our grandiose Hero of the Reformation, Luther).