Surely this could backfire on Halfords massively. As people have already pointed out, buying online is much cheaper and the service is quite often miles better. Personally I use Halfords in the same way I use other big chain suppliers - as a showroom. Take a look around, then if I like a product I'll go home and buy it cheaper online
How much would it cost these small suppliers to ship to internet shops instead, or start selling to the consumers directly? It seems to me that Halfords are making a big mistake here, having tried to advertise ripspeed as "the place to go for modifying", they're now encouraging the major brands (who are still small companies in the grand scheme of things) to go elsewhere!
If the likes of momo, pipercross, K&N etc start turning their back on Halfords because of this they'll have next to nothing going for them. Every single product Halfords sell can be bought for cheaper and higher quality somewhere else. I don't think Halfords are as invincible as they think they are.
I also found out recently that their chain of garages which were jointly owned by the AA were sold off by Halfords, and are now run by the rejects from other small garages and MOT centres (I know this because I saw my local "do any job whenever you like" centre turn into "do whatever we like whenever we feel like").