We bless things because they serve people and in the blessing, we give glory to God. We certainly don’t do that for superstitution.
Perhaps some references will help highlight this.
Blessings are acts of divine worship and sacramentals are “sacred signs by which effects, especially spiritual effects, are signified in some imitation and are obtained through the intercession of the Church.” (cc. 1166-1172). The Catechism of the Catholic Church speaks about sacramentals at
usccb.org/catechism/text/pt2sect2chpt4.htm .
The decree which published the Book of Blessings notes that the celebration of blessings holds a privileged place among the sacamentals created by the Church for the pastoral benefit of the people of God. As a liturgical action, the celebration leads the faithful to praise God and prepares them for the principal effect of the sacraments. By celebrating a blessing the faithful can also sanctify various situations and events in their lives.” (Congregation for Divine Worship, 31 May 1984).
The introduction indicates that “Blessings therefore refer first and foremost to God, whose majesty and goodness they extol, and since they indicate the communication of God’s favor, they also involve human beings, whom he governs and in his providence protects. Further, blessings apply to other created things through which, in their abuundance and variety, God blesses human beings.” (n. 7).
“[T]he Church has a profound concern that the celebration of blessings should truly contribute to God’s praise and glory and should serve to better God’s people. In order that this intention of the Church should stand out more clearly, blessing formularies have, from age old tradition, centered above all on glorifying God for his gifts, on imploring favors from him, and on restraining the power of evil in this world.” (n. 11)
What JMJ Theresa has said about priests and blessings is true
but could be broadened a little.
Again, the Book of Blessing reads:
“The ministry of blessing involves a particular exercise of the priesthood of Christ and, in keeping with the place and office within the people of God belonging to each person, the exercise of this ministry is determined in the following manner:
“a. It belongs to the ministry of the bishop to preside at celebrations that involve the entire diocesan community and that are carried out with special solemnity and with a large attendance of the faithful. The bishop, accordingly, may reserve certain celebrations to himself, particularly those celebrated with special solemnity.
“ b. It belongs to the ministry of presbyter or priest, in keeping with the nature of his service to the people of God, to preside at those blessings especially that involve the community he is appointed to serve. Priests therefore may preside at the celebration of all the blessings in this book, unless a bishop is present at presider.
“c. It belongs to the minister of a deacon to preside at those blessings that are so indicated in place in this book, because, as the minister of the altar, of the word, and of charity, the deacon is the assistant of the bishop and the college of presbyters. But whenever a priest is present, it is more fitting that the office of presiding be assigned to him and that the deacon assist by carrying out those functions proper to the diaconate.
“d. An acolyte or a reader who by formal institution has this special office in the Church is rightly preferred over another layperson as the minister designated at the discretion of the local Ordinary to impart certain blessings.
“Other laymen and laywomen, in virtue of the universal priesthood, a dignity they possess because of their baptism and confirmation, may celebrate certain blessings, as indicated in the respective orders of blessings, by use of the rites and formularies designated for a lay minister. Such laypersons exercise this ministry in virtue of their office (for example, parents on behalf of their children) or by reason of some special liturgical ministry or in fulfillment of a particular charge in the Church, as is the case in many places with religious or catechists appointed by decision of the local Ordinary, after ascertaining their proper pastoral formation and prudence in the apostolate.
“ But whenever a priest or a deacon is present, the office of presiding should be left to him.”