If it were worthless you wouldn't waste your time considering entering the market because your efforts would then be as "worthless" as the currency itself, which does have its flaws.
You are correct in stating that these companies pricehandling methodology is flawed when it comes to the exchange rate. I guess you can't expect them to change with the rate when they know they'll make the extra money off of it.
completely agree, don't know what you are replying to bitcoin being worthless? Of course they won't why would they sell something for 3-5K when they can sell it for 15-20K, but that will be their downfall when a company actually comes in delivers an actual product and charges a reasonable amount, these companies will vanish or then finally be forced to compete, but they will still have a hard time as they have demonstrated that their business model doesn't revolve around the customer.