To counter that though, Morrisons have promotions several times per year where you need a certain minimum spend over so many weeks to get a hefty bonus back.
The most recent one was where card holders were required to spend at least £85 per week in any four weeks over a six week period. I always find it easy enough to meet the minimum spend by, for example, simply topping up my supplies of cat food or canned goods. (i.e. I don't buy anything at all which I wouldn't normally do but I might just buy it a bit earlier to achieve a minimum spend).
Spending that £85 per week (over 4 weeks) got £32 worth of points added to my card. As the system works in 'fivers', that's six lots of £5 (= £30) for me to use straight away and £2 worth of credit towards my next 'fiver'.
I get at least £100 of 'free money' per year that way, as well as getting loads of savings on things that I buy often (such as yogurt and cat food) through the personalised offers I get from my card.
Tesco's Clubcard, on the other hand, rarely seems to save me anything. Their prices are generally higher than those in Morrisons (or Asda) anyway and their 'Clubcard prices' are often only the same as the regular prices in other supermarkets. (e.g. I've seen wines in Tesco with what appear to be big discounts for people using their Clubcards. However the 'discounted' prices have been just the same as Morrisons and Asda charge at their regular prices).
In total, I save at least two hundred pounds per year through using my Morrisons More card but I regard Tesco's Clubcard as a total con.