There are two ways to paste into a cell/table and the results are different. If you select the cell and then click again to enter "text entry" mode (i.e., you can type text into the cell), when you paste it will paste everything into the cell. However, if you select the cell but don't click again, when you paste it will paste into multiple cells in the column. Whenever it sees a carriage return, it will move to the next cell. If it detects that you are pasting comma separated or tab separated data, it will also separate it into separate columns.
Example 1:
The following data will paste into multiple rows in the same column
123 Main St
Anytown, State 12345
345 First Street
This city, This state 01234
Example 2:
The following data will paste into separate columns and rows based on the commas and carriage returns. It sees it as comma separated values.
1,2,3
4,5,6
Example 3:
The following data will paste into separate columns and rows based on the commas and carriage returns. Unlike the first example, I inserted a comma in the first row of the address and it now sees it as comma separated values.
123, Main St
Anytown, State 12345
If it tries to import as comma separated values and that is not what you want, you can override it.