Yougov - only one pay out per person?

I used to do YouGov and in a way I still do, or at least I would do if they would send me some more surveys to do.

I finally got to my payout level of £50 after some lazy years of responding to about half the requests to complete surveys and received the cheque about 9 months ago. In that time, after resolving to do every one that came my way now that I had confirmed they do actually pay out, I have received 3 measly survey requests!

Now it might just be me, but I get the impression that once you've had £50, they're pretty reluctant to give you any more in a hurry. I suppose they need fresh blood, however, I don't seem to be earning anything more in referrals, despite knowing a few people who have signed up with my link.

Well at least I don't have to actively maintain anything so it's worth just doing them as they come in and who knows, in five years I may be getting my second £50 cheque!!