Mobile Web Interface Better Bet on Desktop Computer

One of my house-guests recently wanted to place a bet on-line with tab.com.au using my desktop computer (which has the Firefox for Linux browser). The site reported "You need to have the latest version of Adobe Flash Player installed to access the wealth of features ...". But it also said "You can REGISTER, DEPOSIT and PLACE BETS using tab.mobi if you can't download or update Flash.". This simplified mobile web interface looked a little odd on a 24 Inch monitor, with a small amount of very large text. But my friend commented it was faster and easier to use that the Flash interface they usually used. It does make me wonder why interface designers produce complex "flash" designs, when the punter just wants to quickly place a bet.