Your baby stays baby-sized for only so long. Instead of spending money on a high chair that will be thrown out eventually, you could get this portable, folding cardboard one for a lot less and just recycle it with the little one has outgrown it.
Feedaway is a portable and lightweight version of the traditional feeding chair that can be pulled out for use as required and otherwise folded away flat, making it suitable for traveling and visiting where there is no baby/toddler feeding chair. Suitable for up to 18months and/or to 20kg. Feedaway is made from recycled Visy cardboard, and comes with its own 3 point safety harness and recycled cardboard carry box that is strong enough to withstand the rigours of travel by car, train or airplane. Feedaway also fits in a large suitcase.
This product has just reached the market and is only available in Australia for now (but can be shipped internationally), so stay tuned to the designer/manufacturer for availability in the states.