Lifetime Membership That Isn't

I have used this company at their Chenies site for over 15 years. As a professional gardener I found them useful as their are on the way to my main area of work in Chorleywood. I spend so much there that I paid £15 to join their Gardening Club as a lifetime member (you get 10% discount on live plants). However, I visited today (4th February 2013) and was about to pay, when I was told that the Gardening Club I joined is closed down and I would have to join the new one (yearly basis of £5 and only 5% discount). I spoke to the manager (two other customers were also waiting to complain about the same thing) and he said Lifetime Membership didn't mean my lifetime, but the lifetime of the individual card scheme. This is a CON and surely breaches the Trades Descriptions Act. I wonder if the National Trust Lifetime Membership that I have could also be withdrawn if they decide they need more money - I think not!
I told the Manager I was disgusted and would take my custom elsewhere, as did the two other people about to speak to him. This company will close down within the year if they behave like this - they are already struggling. Also check your till price against what you expect to pay - the tills are often wrong. A friend who goes there said she has complained three times in the last year about over-charging at the till, incurring the ire of the till workers and those queuing behind her.