One of the great inventions of the 20th century was plastics. Plastics mean that we can make very light, disposable containers. Plastics also mean that these containers can be clear. Plant roots don't like light, and I expect that tradition and pricing have also meant that clear pots are not commonly used commercially.
However, for the home propagator clear pots are a wonder. At a glance you can see the size, number, type of roots as the form. However, many plant's roots don't like light so we must shield the roots during the day. A person or company called Hiko invented a wonderful system for growing large numbers of hetrogenous cuttings. There are two parts to this system, firstly, a black plastic carrier holding 40 pots with a smooth surface for easy filling with potting mixing. Secondly, a choice of clear or opaque, flexible (polyethylene?) and brittle insert pots (polystyrene) that sit in the carrier.
Here are some empty inserts I've just taken the plants out. It is easy to crush these pots in your hands if the plant is being difficult, although I generally try to reuse the pot. Due to the number of pots I use invariably a number end up underfoot, where they crush into clear plastic chips with a distinctive snail like crunch. I use these chips as a base for potting mix - they are easy to crush up.
These four photos show different plants in various stages: The first is prostanthera that just recently struck; the second a grass that is definitely wanting to go in the ground; the third a Myrtaceae making its first baby steps; the fourth a giant Bulbine that is about a year overdue.
You can also grow reliable seeds directly in the pots - I grow Allocassuarinas this way as they usually come up, and grasses and Eucs.
When it comes to planting time I have two techniques - stabbing out a hole with a little hand spade (great for Psycho impersonators), or lifting open a slice with a spade and pushing the plant in. Both methods have high success rates. If I were planting these for say landcare I would probably develop something like those stamp planters.