I like how you separated the urls with "[dot]com/" 😊.
he site also offer free accelerator, but obviously it can not work
The free accelerator is a bait, nothing else.
I too or anyone can come up with such idea and use it to scam people. Are they not scam sites?
You will be scammed when you will go for the paid service. They will just take the money you sent.
The bitcoin transaction accelerators that we should believe are the ones owned by mining pool like
ViaBTC accelerator.
So for viabtc is the best accelerator service I have used. Even with their free service you can easily get your transactions confirmed 90+% times.