Hummus is very tasty with tahini made straight from sesame seeds rather than pre-made. I suspect the reason most recipes say 'tahini' rather than 'sesame seeds' is that when you toast the little sods in a little oil they develop a passionate desire to stick to everything, rivalled only by polystyrene beanbag beans. Which is fine if you don't mind licking sesame seeds off your pans (and I don't) but would probably really annoy some people.
*what a treasure trove that place is, the kind of small shop where you can buy road salt, lemons, dog toys, chickpeas, beer, bacon AND deeny boppers.