You can try with this service http://articoolo.com/how_it_works
However, I personally think nothing best your genuine content because it'll also benefit SEO of your Shopify store as well. Earlier or later Google would recognize whether it's "Content generator" machine or natural human language.
I have been writing product descriptions for a while. I wrote some for a client who read this thread and he was happy.
If you need any copywriting services, please contact me via mail, firstname.lastname@example.org.
See you there!
That's true. All well known platforms available are way too expensive. Goes anywhere between $3-$5 even when ordered in bulk.
After some researching I found these guys who are doing it for a cheaper rate. Around 10-20 cents per description. They are small scale but are delivering decent work. But the problem was that I had do rewrite the keywords because their keyword research wasn't up to the mark. Otherwise, the content is decent for ecommerce stores. Here is the link http://adzis.com/landing.html. Pricing starts at $40 for 100 descriptions. For my previous project for an apparel store I got 2000 descriptions written for around $550. The good thing is that they were providing me escrow(not sure it's available for others. I got it after some bargaining) for an additional 5% so that I didn't have to release the payment before I am satisfied with the outcome.