I need a 4ft (if it can be daisy chain) or 8ft LED flush mount light fixture. I need it in my garage. I have tried 3 of the AntLux 72W LED Wraparound Lights 4ft but it's not bright enough. The issue with this one fixture is that it only brightens what's directly below. So that would means I need to purchase a lot more than just 3 and if that's the case, it'll cost too much. In addition, I don't think this particular fixture can be daisy chain. Perhaps instead of just 4ft or 8ft, it could be wider too. In the traditional fluorescent fixture, I believed there are those with 4 to 6 tubes in one fixture. I'm not sure if LED fixture has something like that.

 

The link you provided shows several installation where those lights are daisy chained. One picture shows the ends of the fixtures touching making one almost continuous fixture. Another photo shows them daisy chained with conduit in between.

Light fixtures aren't made much wider than what you linked. Partially I think it's a matter of shipping something so wide. Plus, if you want to spread the light out further you just add the fixtures where you need the light. If you want the light more evenly spread around the room I would consider smaller fixtures but more of them. There are even single strip fixtures that are very inexpensive and only about 1 1/2" wide making it easy to arrange them however you want.