Heshima MbeleMkuu, I agree with your, but in case you haven't notice, both E bay and Amazon or any other online retails in particular, they have options on shipping the device in so many different ways, you can have you item shipped by using DHL, UPS and the alike,and it will take from 3 days to 7 days depends on option you have chosen,
remember you choose shipping method yourself and this will have an effect on your final bill for the payments, if you want your item ASAP then you have to pay more e.g fast track will take only 3 days, ( i always use fast track option when buying item online) and they send it either UPS or DHL
normally for those items that have "free shipping" tag, the seller is not going to charge you the shipping fee, but then he will choose the cheapest shipping method regardless of how many days/month it will take to reach you, and in this case he will definitely choose postal as his shipping method,and you can guarantee its going to take at least a month to reach you, if it will each you at all. i have experience on this, i took almost a month to receive just a simple watch i bought online + hard case for my kindle hdx
In additional
1. if your item is going to be sent by dhl, ups then you will definitely get a tracking number, and you will track you package up to the last point, in weather its DSM or BUKOBA
2. most of the item sold by third part they have a tendency of using postal services, but for the E bay or Amazon themselves, the always use the fastest and reliable shipping agents