I think that's what happened to me when I was roofied, someone doing it for fun or to test it maybe. I was sitting in a bar where I know all of the staff/worked with a handful at another job and waiting for my two friends which was easily heard by everyone sitting around me and I was mostly talking to the bartender (one of my coworkers at the time) or on my phone. Since we were planning on leaving that bar once my friends arrived, I saw them outside finishing a cigarette and yelled at the bartender to grab my drink, didn't watch him do it, and just dashed to throw my bag into my friend's car and got back and got 1/4th of the way through my second beer and my head slammed down on the bar table. I had spoken to NO ONE besides the bartender, but the bar is in this square shape where if the bartender would have had to go around to the other side to serve someone/grab a specific bottle he wouldn't have been able to watch my drink/forgot to put it behind the bar like normally if I leave the front entrance for some reason and can't take it with.

One of the friends I was meeting worked with us at my job and worked with the bartender as well at that bar (so they were coworkers twice over) and GRILLED him half at the time half after I was in the hospital and he swore up and down that I was 100% sober when I came in- he had talked with me extensively and that it was only the second beer I was being served, that no one else spoke to me. I can't imagine even if I had been drugged by someone attempting to do anything to me HOW they would have possibly gone about getting me anywhere or even talking to me. It was more than obvious I not only knew the bartender but the regulars that were sitting next to me (albeit watching a game and not paying attention to me after saying hi) and I was talking about meeting two guys. Bartender said a guy came over to where I had been sitting to order a drink since the bar was full and it left a gap to lean over and flag him down (not that weird) and only then did he realize my beer still sitting on the bar and put it behind the bar so I thought he had it behind the bar the entire time when I came back (this was all pieced together way later obviously, them not knowing wtf was going on took precedent at the moment it was happening. Otherwise I would not have touched it if I thought he never put it away) but I had blacked out and was making zero sense somuch that I couldn't say or explain ANYTHING of use to my friends. They first tried to drag me home but I became really paranoid and violent (allegedly, again don't remember any of this) and hurt them both so badly (not like BADLY but they were getting sick of me scratching their faces and necks) they took me into the hospital after finally accepting I wasn't just trashed where I tore two male nurses to shreds as well while they were trying to subdue me. I was shocked as shit when I woke up EXTREMELY ill and apologized to those nurses for hours who just laughed and said it was better I reacted like that if I were in real trouble. At least if anyone ever does do it again with the intentions of taking me, I'll probably be too much of a little shit for them to deal with and hopefully they'll give up :\ my nails we jagged and cut from scratching the shit out of all 4 guys. At least I'll leave DNA everywhere if I'm murdered.