No you can't do that. Even though the nutritional values are very similar to the asda ones, tesco pittas are stuffed full of additives and are a lot more processed than asda. That's why they don't qualify as HEBs. There is a thread on here that lists the ingredients - I'll go and find it for you.
It's a pain isn't it!! Every time I go to Asda I stock up on the pitta breads, their smart price syn-free natural yogurt and my fave cereal which I can't get hold of at Tesco!