It's a hardware startup that is selling to Hotels. There are barriers to entry, but nothing inherent to being a B2B startup.
Bootstrapped B2C hardware companies face similar challenges.
Hotels are only one business vertical, there are hundreds of thousands of business verticals, some of which won't require as much upfront product investment to gain traction.
It boils down to this: hardware startups need funding to get off the ground.
Here is my unsolicited advice:
Find yourself a business co-founder who has experience in the hotel hospitality space. If you can convince them of the value of your idea, and the sign on, their job is to find a few hotel chains to do a paid-for pilot. This person could even be your first investor.
In lieu of that, raise a friends and family round to generate enough funds to get the hardware you need, and target a subset of rooms at a hotel (luxury room suites). You won't have to buy nearly as many tablets, and their patrons already expect a premium experience.