Personally I think YOU're the lucky one who gets to play real amps rather than a computer hooked up to a PA, but that's just me.
As for another poster's comment about spending money on a good PA rather than amps:
In MY world the only reason for going ampless would be less heavy lifting and a fast, hassle free setup. There are other reasons too of course but the main thing for MY needs would be less stuff to carry. A good PA optimized for ampless/IEM (rather than a cheap, rehearsal space vocal PA) would mean considerably more weight/space than the amps it's replacing. Besides, how often would you actually need that expensive PA you've spent your hard earned money on? Most venues already have permanently installed PAs and smaller venues (bars, coffee shops, etc.) with poor quality "vocal only" PAs (+maybe a DI'd keyboard in a pinch) would most likely not allow you to pull down their rig to make room for your ampless/IEM-optimised PA.
There are some types of smaller gigs where going ampless isn't really an option. At least not yet.
Even with gigs where it can be done without any practical issues I personally don't see many benefits except if:
1) You REALLY don't want to (or can't) carry a lot of heavy gear
2) You rely on a lot of different presets/tones (like a cover band) or presets triggered by a click track (like many metal bands do).
Triggered presets can of course be extremely convenient for SOME musical genres but only for genres where a click track is appropriate. Metal is one of them but for many other genres of music using a click track will completely suck the life out of the music and not really an option.
It's all about finding the right tools for the job. For some musicians going ampless is a great choice. Personally I don't like it very much. I prefer playing real amps on stage and so do every single musician I know outside of metal (although some cover band guys I know go ampless on occasion for practical reasons, even though they don't like it very much).