Scanners arn't really all that expensive - you could get a decent flatbed scanner for under 200 dollars about a decade ago, and my current scanner/printer cost me 30 dollars at a discount.
ADF, however is a feature usually found on more expensive models - the aforementioned cheapie dell does not have it, while the office scanner/printer (a canon pixma) has a full duplex ADF (which is the best thing since sliced bread).The 'cost' isn't scanners - its that you want a less common feature that happens to be on more expensive models.
If you want your scans are not aligned, the problem is probably that you're not loading the ADF properly. Make sure the stack of paper is aligned and resting on the correct side of the feeder. ADF works better with bigger stacks for that reason. Otherwise, i've never seen bending in our office scanner.