Sometimes you can find these adventures in trade.
I enjoy the event achievements and the challenge of managing them all - but they also stress me out because I put pressure on myself to get them all, and in order to do so I often lose sleep time (to get another collectible spawn for example) which I know is stupid and unnecessary, but I still do... I also spend the three weeks of the event worrying about a combination of maintenance, isp, work, family etc meaning I will miss a log in day and therefore miss an achievement (open a calendar, do a guild quest, kill a golum etc).
The regular achievements, I tried hard to get at the beginning, but now the rest seem out of reach or pointless.