The Sunday Rant!

What is it about people at bootsales. I was up at an early one today at 6am, hordes of people there and looked to be a great day at first. I had 400 cards to sell, all handmade and priced at £1 each, 6 for £5, 9 for £7 and 14 for £10. So best price was just 73p a card. People were coming up and picking up bundles of 10 and offering me £2. How do they expect me to make a card for 20p, I was offering discounts off the bat but giving them away for that price was ridiculous.
To be fair there were some good buyers there too, who recognised the value in them and I came away with just over £120 in three hours which all in all is pretty good. Certainly much better than the recent craft fairs I've been to where attendance was extremely poor.
Has anyone out there got any ideas and tactics to maximise your sales at these events. Please comment below.