Yeah but that's like saying Dodge is missing out on selling 69 Charger replicas because you own a couple originals. To make that, it'd cost X and they'd have to sell Y to be profitable... Just because you are buying old ones and want them to do new ones doesn't mean that's a good idea for them, or that it's going to make them $ guaranteed.
That might be the worst analogy. Ever.
Look, the "We can't make enough money on this" bit is so tired and overplayed and frankly, lazy. These things have a fixed cost. If you need to make more profit from them because you estimate low volume, then charge a premium. Make it an exclusive. It can't possibly sit around any more than a number of the random vehicles like Finn's Dunebuggy or even Ray's Speeder that dropped down to $5 clearance. People said Hasbro couldn't make a 6" line work at $20 either, but that line is constantly in demand outside of stores that get bogged down with Zuvios and Finns, and I know zero kids that are collecting 6".
I don't want to get on a bash Hasbro session, but I seriously doubt they have any solid data on how much of their product gets purchased by collectors vs. kids. I know kids that have Star Wars toys and my collection is easily 100 times beyond what any of them has. You would need an awful lot of kids to make up for the buying power of a serious adult collector. I work in Consumer Research for a CPG company and in many cases you have 20-30% of the buyers accounting for 70-80% of the volume. I'd be surprised if Star Wars was much different. I've never once been polled or surveyed despite 20 years of collecting and daily activity posting about Star Wars toys and neither has any collector that I know. Exactly what data is Hasbro basing their analyses on? And this all assumes kids don't like playsets - you know, like the ones Lego constantly sells out of.
Conversely, think about the added benefits from selling playsets. Collectors and kids already have a plethora of figures and ships. Each additional ship or figure can become diminishing returns, but a playset could be new and more appealing. It's also a companion piece to the rest of the line. If someone buys a playset, they're likely also buying a few figures to join it. Sure, many would have bought figures anyway, but there's a level of incremental figure sales that accompany ships and playsets. Making them modular can drive "army building" as well, so you'll benefit from some people buying multiples, whereas it's unlikely that someone is going to stock up on most characters or ships. There's a lot of rationale that these could succeed in the face of a blanket "playsets aren't profitable" stance.
Getting off my soapbox now...