Some restaurants only use Uber eats and other 3rd parties as they don’t have the knowledge, the technology, or the staff to do it themselves. Particularly if they are just starting out or are unsure about new technology.
They tend to have to increase prices to pay the 3rd parties or risk going out of business. All takeaways would prefer your business direct if possible. If you like them, try and do that where possible.
Imagine you pay £6 for a curry, Uber eats gets almost £2 plus the apx £3? delivery fee to pay the driver.
The restaurant only gets £4 and from that they have to pay the rent on the shop, the ingredients for the dish including seasonings, oil etc, the chef, including their pension, national insurance and holiday pay, the cleaning staff, blue roll, sanitiser, the business rates and permits, the gas and electric, the boxes and napkins and forks and sauce sachets, insurance, marketing costs like flyers and Facebook ads. Oh and of course VAT is normally 20% so that’s already £1 from the total.
Barbera is right. Just Eat are absolutely raking it in.