Seed catalogues do not only go to the home gardener but also to farmers and nurseries who want larger quantities of seed. To print a separate catalogue for each would be expensive in time and cost.

I'm sure most have smaller quantities and if they don't you are dealing with catalogues for large seed orders only.

For some seeds--like Impatiens-- I like that larger quantities are available and that the more seeds you buy the cheaper the price.I can buy 250 seeds for $8 when it would cost 10 times the price to buy them in small packages of 50 or 25 seeds

There are lots of seed companies so find one that sells seeds for home gardeners and over look the larger quantities available.

I think the main reason that commercial packets of smaller seeds have so many seeds is related to marketing and customer satisfaction. The seeds, in the case of something like carrot seeds, cost very very little to produce. Most of the cost is related to packaging and marketing. It might cost less than a penny for the seed company to add all those extra seeds. The difference, or the reason that the company chooses to have so many seeds, is that many customers would feel ripped off if they opened a package and only saw what turned out to be a hundred seeds. It has nothing to do with how many seeds you need; it's all about whether you are satisfied with the packet (if you are picking the packet off the shelf for purchase) or with what you see when you open the package (if you already bought the seeds and are a potential customer for more seeds next year - most people don't save the extras anyway).

There are places that cater to the home gardener. Look at The Sample Seed Shop, for example. I order every year from them and the quantities are perfect for a year's worth of planting plus mistakes. Very generous.

What I've done in the past if I've ended up having to buy a large packet to get a variety I wanted is swap!

Here is a link that might be useful: The Sample Seed Shop

You might want to try Pinetree seeds too. They have a tendency to have somewhat smaller sized seed packets that are reasonably priced.

Since, as has been discussed, the prices are no higher with the larger quantities, why worry about getting smaller packs. Nature "wastes" far more seed than we'll ever dream about (ie it's not irresponsible and doesn't make you a bad person). Just use what you want and either discard the remainder or give them away on the Seed Exchange Forum.

First not all seeds come up. Second, you might have to resow because slugs eat your lettuce. I had to resow peas three times this year and still got no peas because mice like pea seedlings.
And carrots or lettuce for example you sow several times per year to have a supply as long as possible.
I hate when seed packets are too small. I expect to have at least a year's supply from one packet. Carrots I can sow most of the year here and you use them often in cooking. I sow a row of lettuce as soon as I come around to. The best thing is to sow always a little bit of everything and some weeks later a bit more.
I sometimes even buy commercial packets because they are so much more value. Some seeds I safe myself.

Chiming in for Pinetree here - been a satisfied customer for many years - & their prices reflect the smaller seed amounts.

Here is a link that might be useful: Pinetree Garden Seeds

Once seeds get small enough, or odd ball shape, it is impossible for machines to count them so they then use weight. With extremely light seeds it takes a pile to even register on the scale. As someone else pointed out the packaging often is worth more than the seeds, so why bother worrying if you put a few too many in.

Save them, trade them or just give them away.

SCG