I get paid when ever i get called out, I also get paid for each call, and paid for being on call. The number of incidents probably decreased not because they were made up but due to various other reasons, first being there is less incentive to make sure things are running ok and there are no possible problems before you leave for home. Also when there are smaller things that really could wait until the morning if you are paid to fix it, you go, if you are not paid, you just wait until the morning.
I try not to have to go in when called as i live 40 minutes from where I work (no remote access to the production systems), usually it occurs in the middle of the night and i still have to go in the next day. But if its a few hours before i have to get up, and i know i will not get back to sleep or its pointless trying i will go in, get the pay for fixing it and then start the days work and go home early.