Yes they do, I bought my iPhone outright (contract-free) from Maxis centre TTDI a few weeks back. They just told me to get a Hotlink prepaid pack with it, and now using it with my Celcom line no problem.
If any Maxis centres tell you otherwise (must buy with contract lalalalalala) they're just BSing you (or have run out of their quota of contract-free iPhones).
Problem is, stocks are VERY limited and contract buyers are prioritised. So, your best bet for a contract-free purchase is to get it from the MAIN Maxis Centers in KL (KLCC, Midvalley, Pavilion or TTDI), and line up REALLY early in the morning.
Also some forummers have reported success getting a contract free iPhone 4 from the Alor Setar Maxis centre (also with a hotlink pack).
Or get it from other shops, but problem is they mark up the prices. You should get it for the RRP from Maxis centres (I got my 32GB for RM2690). Any more and they are pocketing the difference lol.
Check the Maxis buying thread for more info and updates.
i've already went to klcc maxis center and they told me i must purchase it with contract. frustrated, i went to lowyatt and bought sing set for RM2500 16Gb...2010 price... urs RM2690 for 32GB...very good price indeed....