I plan to travel to Morocco later this year and wanted to check if anyone with previous experience getting a travel visa can shed some light here. The Embassy of Morocco in the UK states that for a travel visa, the following documents are required (among others):
Copy of your detailed provisional flight itinerary.
Hotel provisional reservation or notarized Letter of Invitation
from your sponsor in Morocco.
I tried to call up the Moroccan Embassy in London for a few weeks but they never attend to phone calls! I consulted with a visa service agency based in the UK called CIBT and here's what they told me (since this is not an official response, your mileage may vary):
Your hotel reservation does not need to show payment has been made in full. All it needs to show is that the booking has been made for the period you plan to stay in Morocco.
Bookings made through any online travel agencies such as Expedia, Travelocity, et al are allowed. I'm not sure whether this covers Hostelworld too but I don't fundamentally see why it should make a difference, unless they are biased against hostel bookings.
I got my visa without any issues, without having to splurge on making fully-paid hotel bookings.