Vendors not stocking parts they advertise

I ordered a Borgeson power steer conversion box from Summit and after about 3 weeks it hadn't shipped. I called them and they said they have no ship date. Got sick of waiting so I cancelled order. Found part on Jegs and it says ship tomorrow so I thought (stupidly) I would order from there as they may have one. Well what do know they don't have it either. After a couple weeks I got a Email saying will ship 6 April. April 6 came and went no part. I called them and they said the part is about 6 - 8 weeks away. Ok left it on order and called them again today after 4 weeks and the rep says OH that part is 6 -8 weeks away - WTF. In the meantime I saw this part on Ebay so I emailed the guy "Do you have this part in stock" One word response "NO". I dont know how these vendors get away with selling parts and holding your money without providing the part or a firm ship date. I am extremely frustrated as this is the only part I need to finish my Duster as I have clearance issues with my TTi's - Dont get me started on that one again.
i agree its wrong, cause you know they put that money in the bank and gain interest on it while waiting to ship your parts.