Back around No Control/Generator/Recipe, BR were still doing encores. Greg's usual response was "Don't you guys remember, we don't do encores...That kind of shit is for rock stars... You're just lucky we forgot to play a few".
In the Stranger Than Fiction Tour (Santa Monica) they played their 'last' song, then Greg explained they don't do encores 'cause that's for fuckin' rock stars and he said "So tonight, we are not doing an encore". They played three more songs and left. The next night's show had no encore and it was that way for about 6 years.
I have seen a whole audience shouting "bastards" in unison (a festival in Granada, Spain, April 5, 1998) because they weren't coming back for an encore (and had only played for 50 minutes). I asked the band to go back and play an encore but they didn't. "We never play encores". Brian called playing encores "a throwback to vaudeville".
Then, at the first Sao Paulo show on March 3rd 1999 they did play one: Fuck Armageddon. They turned on the lights and everything, came back out and Greg said "we usually don't do encores, but we'll play one more".
And in the year 2000 they started playing encores regularly again. Greg said in a show on April 13, 2000 (in his usual taking-the-piss tone of voice) that "we used to do no encores back in the 20th century, but since in the 21st century we're running out of time, who knows, we may become extinct before we get to do an encore".