The answer to this is...it all depends!
I’ve done the same thing – got a VA credit card and flying club account in order to collect the points, as my previous cashback card (
Amazon) had its rate for non-Amazon purchases slashed. The new rate worked out at about 0.25%. Cashback cards are few and far between now, as people have mentioned Amex is about the only other one left. But Amex isn’t for everyone.
VA flying club points via the credit card work out at 0.5% cashback, e.g. £1000 spent on credit card gives you £5 off a flight. Tesco Clubcard points vouchers converted to VA miles work out at 1.5 times the voucher face value, e.g. £12 in vouchers gives you £18 off a flight. (These rates are from memory – I worked it all out in detail recently, I’ll check later tonight and edit this if I’ve not remembered it correctly).
Yes, if you use a general cashback card like Amex you are free to spend the cashback on whatever product you want, you’re not tied to VA. But if you’re committed to be going to WDW again in the not-too-distant future, you might as well save money this way. It will only be beaten by promotions that give cashback of over 0.5%. For me, VA is really the only practical way of getting to Orlando anyway, I'm not likely to use another airline. Options are limited from Manchester.
At the end of the day. This is *
cashback*. It’s a bonus, anything you get is better than nothing! However, of course it’s all a con. Prices are artificially kept artificially high in order to pay for these so-called loyalty schemes (cashback, supermarket point etc). If you don’t play along and take advantage of the loyalty schemes then you lose out because you’re paying the higher prices without getting any benefit. The only way to beat the system is for everyone, en masse, to suddenly stop using loyalty cards, cashback credit cards etc, and shopping around.
I also get the impression that getting “free” flights via miles schemes is not the bargain you think it is. You still have to pay all the taxes etc which may well be half the cost of economy flights. Whereas if you just use miles as part-payment the money comes off the entire amount. So it’s maybe not worth using your points for a free flight and waiting for them to be released and maybe not finding what you want, it may be better value using the same points just as part-payment and in any case certainly worth it for being able to book the flight as and when they’re released generally instead of gambling on the limited availability of free flights. This theory is untested though so YMMV! Perhaps the free flights take this into account so the number of miles you have to get for a free flights excludes the mandatory taxes. I don’t know.
Be careful that you don’t collect more points than you need, if you’ve got other ways of getting cashback. For example, you can only redeem VA miles in batches of 3000, which gives you £18 off. If you know you want to book a flight in 5 months time and can calculate that you can collect miles to get you to the next 3000-mile boundary in 2 months, for the last 3 months you might as well switch to another cashback method as you won’t be able to use the additional miles you collect. Until your next flight of course, but that may well be 5 years away perhaps! As I said, it just depends on individual circumstances and whether it suits you to collect miles via a credit card at any particular point.