Why offer the shop in different languages ?

You sell to France, Italy or Spain and other countries ? ... or your customers are of a different mother tongue ?
Then it is very important that you provide your customers with an orderly and comprehensible ordering process.  This will immediately minimise incorrect orders and, above all, aborted purchases, as the entire order process is displayed in the customer's native language. 

Ask yourself ? 
Where would you like to order if you need goods from abroad....? in a shop where you see the articles and want to buy, but do not understand the order process, or in a shop that is in your mother tongue or learned language and you know what you are clicking on and under which conditions !

The icing on the cake are the e-mail confirmations and forms that your customer receives in their own language, because now they are sure that they have ordered correctly and see that you are making an effort.
and sees that you are making an effort to serve your foreign-language customers correctly.

PS: By the way, the main markets for goods exported from German platforms are...France, Spain, Italy, Netherlands.... (Source:translate2019)