I wouldn't do that either. "Getting in trouble" is the general problem. Specifically, any immigration officer that detects that that has happened would be lead to wonder if there was a reason other than just needing more room that you did so. For example, another poster mentioned that he had a full-page visa sticker from Cambodia. Even if you are traveling on an e-visa, the immigration inspector upon arrival might detect a peeled-away page and wonder if it was a prior Camodian visa with something on it that you didn't want him to see.