Peppers have tendency to cross pollinate easily. Also, since I've been saving my own seeds, I have experienced many instances of stray seeds and lost labels -- in much smaller amounts, of course.
So, when I see unidentified mix like that I suspect one of two things -- that either they are a mixture of stray unlabeled sweet varieties, or that some peppers were grown together in a same bed and resulting seeds are suspected of being result of cross pollination.
That said, two popular sweet pepper varieties with big fruits that taper to a point which come to mind immediately are Italian frying peppers like Corno di Toro and Giant Marconi. (Hmmm.... Just looked around to verify, and Giant Marconi seem to have blunt end) They both come in red or yellow at fully ripe. I have a variety called Tolli's Sweet Italian (red) that has the blunt end. But there are others, and they could be results of cross pollination, not true to any single variety.
There are peppers with various degrees of heat for roasting and grilling that grow to same shape as well (one example would be Numex Big Jim), but hopefully, they were correct that all the seeds in the packet will grow sweet peppers.
How tall are the plants? If short, I also have two varieties growing called Donkey Ears (red) and Doux Long d'Antibes (yellow) that grow similarly shaped peppers.
Learning never ends because we can share what we've learned. And in sharing our collective experiences, we gain deeper understanding of what we learned.