I would, too.
William Shatner is a genuine TV legend (and I don't like to use the word "legend" lightly unlike a lot of people). His body of work is amazing. I've got a talk ticket and will be purchasing an autograph at the con. I'm really excited. Never thought I'd get a chance to meet him, and he's 79 so this is very much a once in a life time oppertunity.
Considering all the iconic things he's been in and the fact he's not getting any younger, I've got no issue at all with paying a few quid more than usual. People whinging about the price are being really unfair toward those who are able and willing to pay. Especially since there's still a few months to save up.