Yes, people don't always know the difference between a named seed strain and a cultivar that must be asexually propagated.
I think this practice contributes to that confusion: some seed traders will write "OP" on a seed packet, intending to convey "the pollen parent of THESE SEEDS is whatever the wind and insects happened to blow around". They might be isolated, or might be planted shoulder-to-shoulder with cousins and hybrids.
But the seed recipient sees "OP" and thinks "Oh, good! It must be an OP VARIETY
, hence not any kind of hybrid or unstable cross. Good, it will come true from seeds, so I'll just bag my plant and re-offer the seeds with the name that was on the pkt I received".
The next trader gets F3 seeds but doesn't know how off-brand they are unless they look up the alleged variety and notice that their "OP variety" is really some generations after an F1cross.
Now that I know how differently "OP" is used by different people, I assume that any traded seed is cross-pollinated unless the trader spells out the isolation method used.
And I Google the variety to determine whether F1 or open-pollinated-VARIETY.