An interesting aside to this discussion, perhaps a bit OT, but close -- modern
cultivated pineapples are seedless only because they are strongly
self-incompatible (cannot use pollen from the same cultivar), and they are
planted in solid blocks of a single cultivar. Plant any 2 cultivars side by
side, and you get lots of seeds. A significant problem for the hobbyist
grower, who wants several varieties and grows them in a small area. I rather
suspect the same thing would happen with "unimproved" wild types, since
self-incompatability is common in the wild, for encouraging outcrossing.