Differences Of Terminology Regarding Matters Of Acts
These two cases are not analogous in any way. To please someone is a good act, so no question about its beign allowed or not, and to do a duty, even if a religious one, is allowed to have a monetary compensation against the time it demands.
Yes of course, if you earn love for your help, it is ok, if you demand monetary compensation it is ok. The question should arise when there is something immoral or unethical involved and this your sense of morality indicates.