[habitue]

As others have said, it's an old sales tactic that benefits the seller. You'll see it mostly in places where:

1. There's not much competition for the product, so the seller has no reason to compete on price and make things easy to compare

2. The sales process / cycle for that industry requires so many stakeholders and agreements etc that pre-committing to a price range up front is just an unnecessary handicap. They'll be in negotiations with numerous executives with a prospective buyer potentially for years before getting a signature. In these situations the buyer is not a naive consumer, they're a corporation that can take care of themselves and giving out the price is a free point in that game.

3. They haven't sold anything yet. They are still in the research phase and are feeling out what people might pay.