The cost of obtaining a single or a block of static ip addresses is still rather high and may not be available for business owners that operate from residential locations.
In order for the smaller companies to serve their own web pages and have their own domain mail, they will have to make the decision of either to get their domain hosted, get a static ip plan or make use of the dynamic ip addresses that they are allocated with.
Having the domain hosted would save companies intending to get a web presence a lot of headaches but leave them with very little flexibility on the kind of pages they can serve on their hosting company (namely difference in Windows hosting and Linux hosting).
Besides that, there are also restriction on number of email accounts, web space allocated which also covers the space required for your mailboxes. Business will now usually host their mail separately on Microsoft O365 and then website elsewhere.
Alternatively, for ease of managing and reducing possibility of data leaks, business can self-host on a static ip broadband connection which is usually more costly and there is no service level assurance. Server security and patches also need to be handled internally.
When static IP is not an option, utilising a dynamic DNS service provider that would allow you to periodically update your ip address on their DNS servers with an updater software and achieve the option of keeping your data within your network. If hosting email is required, a backup mail server (relay) will be necessary to hold you mails in event that your connection is down.
We have even done email hosting on Mercury mail server at one period for a truly low cost option.
With the increasing speed & decreasing prices of business Internet plans coupled with and high speed fiber offered by ISPs, servers running behind a dynamic IP plan hosting cameras, network video recorders, remote access and simple web applications is rather common.