In every situation where choice is involved, we must choose which act is more important at the time, whether the act may be postponed, etc. One aspect of "small acts of sacrifice," in my opinion, is, if we are doing them "correctly," we are not able to recall them to mind very readily, nor do we dwell on them, because they should be routine, a habit. We forget them quickly.
Yes, they do fade rapidly into memory. I agree that it is good to pause before taking a particular action and consider for whom we are doing it. This can sometimes get tricky when something might facially benefit another, but may also pander to a selfish impulse.