You make this sound as if every body in the site is sending support emails at once. Be realistic. These sites don't get that much emails. It totally dosnt make sense to delay a reply for up to 24hrs. Safedice for example hvnt replied to my email and this is 3rd day.
There are SMRT phones to enble u communicate on the go. If they hve time to recieve deposits, they should have time to rply emails
Receiving deposits and processing withdraws are usually automated. They run a program for those things, but they can't write a bot to automatically process support tickets. Just wondering, but what did you email safedice about? 3 days is a little long, but you can't expect every site to respond to support tickets on 3 hours, as the staff might be busy on something. Under 1 day is good imo