restaurants or indoor events (without flash)
You might find that 2.8 may not even be enough for many situations like the ones you mentioned above.
You might want to look at fast primes if you're leaning towards available light photography. One of the reasons which pushed me to using primes exclusively now... (my wife appropriated my 17-55/2.8 as her own now :bsmilie: citing reasons of underusage by me)
(below I shan't quote the older non-AF lenses, although there are some with definitely wider apertures)
Cheap(er) alternatives would be like the 50/1.8 and 85/1.8
Other more expensive alternatives include... 35/2 50/1.4 85/1.4 105/2 135/2