Cheating can take from others.
Merit scholarships are given based on class rank. If the #11 student cheats to get to #10, then they took scholarship money that someone else actually earned. This is a very real problem in my school district.
Additionally, if you cheated to get good grades and got into a good university because of them, then you probably took the seat of someone that didn't cheat and was not accepted but would have been.
Also, (some?) universities internally rank high schools by the performance of the students they accept. So, if School A sends a bunch of 4.0 students that all flunk out, then future students from that school get their 4.0 weighted lower than a 4.0 from School B where students regularly graduate from the university with honors.
So, if you are cheating to get a good grade and you get into a good school (taking the seat of a student that didn't cheat) and then you get caught cheating, or just end up doing poorly because you were never that good of a student, then future students from your high school will be penalized because of the poor choices you made (and because the school was unwilling or unable to deal with those choices).