This must be channeling some of the turn-back-the-clock energy in Catholicism, the selling of pre-printed Mass cards. The Irish government clamps down on it, and the Irish prelates are grateful. Bishop Colm O’Reilly of Ardagh and Clonmacnois in a CNS interview:
I don’t like to use the word scam in relation to the selling of pre-signed cards, because I don’t want to make people who bought the cards feel guilty that they have done something wrong, but many of the cards that have been sold are not authentic. My biggest problem with the sale of pre-signed Mass cards is that it is disrespectful of the profound meaning we have in the Eucharist.
In parish life, many people who have Mass intentions will actually come to the liturgy and pray with the others in the community. I think that maintains the respectful element. I also know that some parishioners donate larger sums and line up a whole series of Mass intentions. They have their reasons, I guess. While I wouldn’t ever consider doing that, I know the practice is deeply ingrained in a few Catholics.
Then you have the assignment of an intention to a Mass being celebrated by a mission priest somewhere in the world. Money changes hands, and heaven knows the mission apostolate needs resources. A prayer is said for a loved one. One trusts an intention is offered far away, and maybe the reception of money being put to good use is prayer enough.
In my thinking, which you may judge Protestant or non-Catholic, the Mass intention by means of donation or designation is hardly relevant. My counsel would be to go to Mass on the special day. Or even when the intention comes strongly to one’s mind. If one celebrates Mass regularly or even daily, go early: add some sacrifice of time or effort. Pray for one’s intentions before liturgy. Mention them again in one’s consciousness when the prayers of the faithful are offered. Speak one intercession out loud if the priest gives that option. Pray after the reception of Communion. Pray after Mass is over. There are drawbacks: no cash or cards exchange hands, no priest has uttered the name of the beloved, and a sacrifice of time is required. But does faith inform us this method is any less effective than buying a printed card from an Irish street vendor?