Since I am producing own bicycle restoration Stickers (mainly Marin, Syncros, Ringlé, Answer Manitou, KLEIN etc.) I can tell you: YES! it is NOT profitable at all! Investments for machines, software, tools and time is in no case in good relation to sales numbers and the effort you put into the ads, the e-mails, the customers service or the time you need to pack things and carry them to the mail box.
From a business point of view I can totally relate to their decision. Especially since they have superb range of options and materials and therefore a truckload of machines to run all that. I myself am doing 90% vinyl cuts only - and with them you can already see that its not a very profitable field at all.
Example: I put plenty of time and money just to be the one guy who produces SYNCROS powerlite fork decals or the hammer n cycle stickers for the stems and the back of the Generation 1 seat post etc.. Expected sales numbers per year? Maybe 2 sets? 3 sets of powerlite fork? 20 sets for stems or 7-10 of the seat post stickers. And that goes for 75% of all your products in your palette. I invested lets say 250,00 Euros of time and material per sticker (!) and expect to get back 25,00 Euros per year. Each stickers will amortise after about 10-15 years! Hilarious.
Most customers simply dont understand the work ou need to do until you have finished stickers or vinyls. Yet they come to me 25 times a month asking me to make a one off restoration sticker for them! And expect it to cost 3,00 bucks or 10,00 bucks a full set!
Now, what does my whole afternoon in front of Adobe Illustrator (for just one sticker) cost? 200,00? 400,00 bucks? And what do you now expect a sticker to cost?
If you would be honest to yourself: "Yes, its basically all just not worth it!"
I myself just do it because I simply want to!